Machine for smoothing fasteners



June 15, 1937. G, SUNDBACK 2,083,930

MACHINE FOR SMOOTHING FASTENERS Filed July 21, 1934 2 Sheets-Sheet 1 III ll Gideon Sundbaoli I ORNEYS.

June 15, 1937. e. SUNDBACK 2,083,930

' MACHINE FOR SMOOTHING FASTENERS Filed July 21, 1934 2 Sheets-Sheet 2Fig. 5'.

l I I INVENTOR.

Gideon Sundbac'k 9 1 RNEYS.

Patented June 15, 1937 PATENT OFFICE MACHINE FOR 'SMOOTHING FASTENERS.Gideon Sundback, Meadville, Pa., assignor to Hooklcss Fastener Company,Meadville, Pa., a corporation of Pennsylvania Application July 21, 193 LSerial No. 736,370

6 Claims.

-My invention relates to a method of and means for smoothing thesurfaces of metal slide fastener elements after they are attached to atape stringen' In the manufactureof slide fasteners, a large number ofsmall metal elements must be accurately formed to shape and attached toatape inclose-ly and accurately spaced relation. This must all be done ata comparatively low cost and it has been found moreeconomical to attachthe fastener elements directly to the tape stringer in a single machineimmediately after they are cut and formed. This gives no opportunity tosmooth or finish thesurfaces of the fastener elemerits except in someinstances by swaging dies,

which are troublesome and expensive.

It has been proposed in a prior patent application of mine, to tumblethe fastener stringers, after the metal elements are attached to thetape, in a loose mass of abrasive particles. While this practiceis'satisfactory to a certain extent, it has some disadvantages which thepresent invention aims to overcome. For example, in tumbling continuouslengths of stringers or several short lengths, the mass of stringersbecomes tangled and balls together so that they are difficult tostraighten out. Furthermore, this does not permit efficient action ofthe abrasive particles.

According to the present invention, I pull continuous lengths offastener stringers through a loose mass of particles. Preferably I alsoagitate the abrasive particles and wash the tape during the process.

In the accompanying drawings, I have shown for purposes of illustrationand description one embodiment of a machine for carrying out myinvention in practice. In these drawings:

Fig. 1 is a top plan view of a machine con- 40 structed in accordancewith my invention;

Fig. 2 is a side elevation of the same machine;

Fig. 3 is an end elevation of the same machine;

Fig. 4 is a fragmentary section through the drum and container of theabrasive particles 45 taken in the direction of the axis of the drum;

Fig. 5 is a fragmentary cross-section;

Fig. 6 is an enlarged view of a typical slide fastener stringer;

Fig. 7 is a section on line ll of Fig. 8; and

Fig. 8 is a plan view of guide member and flanges.

The machine illustrated comprises suitable framework and bearings forsupporting the rotary drum l0, turning on a shaft ll. This 55 drum isdriven through suitable gears l2, I3

from any suitable source of power. The speed of the rotation of the drumis comparatively fslow, although if the drum is made three or four feetin diameter a large output will result.

The drum is' partially surrounded by a perforated or screen walledcontainer M which is also supported by suitable bearings on the. shaftII. This container is oscillated by means of a crank l5 mounted on theend of the shaft 25, and operating through a link l6 connecting theshaft and the container.

The wall of the container is spaced a short distance from the outersurface of the drum so as to provide space. for abrasive particles suchas those indicated at IT. These abrasive particles may be of anycommonly known shape. Preferably, I employ a variety of shapes of smallsteel members, such as small cylinders with sharp corners, conicalpieces and spherical balls with an annular disk, and plain sphericalballs.

The lower part of the drum l0 together with the oscillating screenwalled container l4, operate in a bath 26, which thoroughly cleans thefastener stringer and carries away any dust formed through the action ofthe abrasive particles on the fastener elements, and also acting more orless as a lubricant.

Supported above the drum on suitable standards I8 is a stationary guidemember I9, which has guide flanges shown in Figs. 7 and 8, between whichthe stringer passes. These guide flanges are arranged at a small anglerelative to the plane of rotation of the drum in order that the.stringer can be threaded onto and across the drum. In Fig. 1, it will benoted that the stringers lead into the guides at an angle in order thatthey may be shifted to the next position on the drum. The same standardalso carries a shaft 2| which has three pulleys 22, 23, 24. The fasteneris fed over the first pulley 22 and goes onto the drum at the left handside as viewed in Figs. 1 and 3. Approximately midway of the drum thestringer passes over the pulley 23, the stringer being twisted so thatit will be inverted as it falls back onto the drum. This exposes theopposite side of the fastener elements to the action of the abrasiveparticles. The stringer progresses across the drum and discharges overthe pulley 24.

The operation of my improved machine will now be readily understood. Itis merely necessary to feed a continuous stringer into the machineandhave it automatically discharge the finished product. The fastenerelements are forced through the abrasive particles several embodiment ismerely for the purposes of illustration and description, and that otherforms may be devised within the scope of my invention as defined in theappended claims.

What I claim as my invention is: 1. A machine for smoothing the surfacesof slide fastener elements on the edge of a tape stringer, whichcomprises a holder having a rigid surface against which the stringer isheld so as to expose all surfaces of the metal elements except thosecontacting said rigid surface, and means for subjecting the exposedsurfaces of the fastener elements while so held to the action ofabrasive particles, andmeans for inverting the fastener stringer duringthe process to expose the surface of the fastener elements which wasfirst in contact with said rigid surface.

2. A machine for smoothing the surfaces of slide fastener elements on atape stringer, comprising a perforated container, abrasive particles inthe container, means for continuously supplying cleaning fluid to theinterior of said container, and means for positively guiding and forcinga continuous length of stringer through said container in contact withsaid abrasive particles.

3. In a device for smoothing the fastening elements of fasteners of thetype having a flexible tape and fastening elements secured thereto, thecombination of a container for abrasive particles and a support in saidcontainer having a rigid surface adapted. to support a continuous pieceof tape throughout its surface, said container having openings in itswalls permitting entrance and exit of cleansing fluid, and a bath ofcleansing fluid in which said container is submerged whereby saidflexible tape is subjected to a continuous washing action.

4. In a device for smoothing fastening elements of complete fasteners ofthe type having a flexible stringer with fastening elements securedthereto, the combination of a container for a loose mass of abrasiveparticles, a drum in said container having a rigid cylindrical surfaceadapted to support a substantial and continuous length of stringerthroughout the entire surface of the stringer, means for rotating thedrum to carry the stringer through the particles while supported on saidrigid surface, and means for continuously guiding a stringer to one sideof said drum and removing it from the other side of said drum during therotation of said drum.

5. In a device for smoothing fastening elements of complete fasteners ofthe type having a flexible stringer with fastening elements securedthereto, the combination of a container for a loose mass of abrasiveparticles, a drum in said container having a rigid cylindrical surfaceadapted to support a substantial and continuous length of stringer, andmeans for feeding said continuous stringer to one side of the drum andfor removing it from the other side of the drum during the rotation ofthe drum, and means for oscillating the container to agitate theparticles.

6. In a device for smoothing fastening elements of complete fasteners ofthe type having a flexible tape and fastening elements secured thereto,the combination of a container for a loose mass of abrasiveparticles, adrum in said container having a continuous length of fastener tape woundhelically about the drum, means for rotating the drum to movethe tapethrough the abrasive particles, means for continuously supplying thetape to one side of the drum and removing it from the other side, andmeans for reversing the tape to expose both sides to the abrasiveparticles during its movement.

GIDEON SUNDBACK.

